1. Field of the Invention
The present invention relates to the field of liquid crystal displaying, and in particular to an LED (Light-Emitting Diode) light bar and a side-edge backlight module using the LED light bar.
2. The Related Arts
Liquid crystal display (LCD) has a variety of advantages, such as thin device body, low power consumption, and being free of radiation, and is thus widely used. Most of the LCDs that are currently available in the market are backlighting LCDs, which comprise a liquid crystal panel and a backlight module. The operation principle of the liquid crystal panel is that liquid crystal molecules are interposed between two parallel glass substrates and the liquid crystal molecules are controlled to change direction by application of electricity in order to refract light emitting from the backlight module for generating images. Since the liquid crystal panel itself does not emit light, light must be provided by the backlight module in order to normally display images. Thus, the backlight module is one of the key components of an LCD. The backlight module can be classified in two types, namely side-edge backlight module and direct backlight module, according to the position where light gets incident. The direct backlight module arranges a light source, such as a cold cathode fluorescent lamp (CCFL) or a light-emitting diode (LED) at the back side of the liquid crystal panel to form a planar light source that directly provides lighting to the liquid crystal panel. The side-edge backlight module arranges a backlight source of LED light bar at an edge of a back panel to be located rearward of one side of the liquid crystal panel. The LED light bar emits light that enters a light guide plate (LGP) through a light incident face of the light guide plate and is projected out through a light exit face of the light guide plate, after being reflected and diffused, to thereby transmit through an optic film assembly and form a planar light source for the liquid crystal panel.
In the conventional side-edge backlight module, due to the requirement for slim bezel, two sides of an LED light bar must be set inside the active area (display zone), and this leads to a dark zone at corners of the light guide plate. When 3D is realized through application of dynamic scanning mode, it often needs to include a micro-structured light guide plate that imposes confinement on light. Under this condition, the corner dark zone becomes severer for the length of the dark zone is increased. This severely affects the performance of displaying.